The idea of voided flat plate slabs already existed in ancient times. Even then, it was clear to the designers, that solid constructions exerted too much of a load, making large spaces impossible.
One of the earliest examples of a building that was not solid, is the Pantheon in Rome; „Cassettes“ in the slab construction reduced the overall weight – the ceilings could be designed to span more generous expanses. For larger buildings, this voided principle was used into the middle ages, and it is still used today.
In the mid-1990s, the idea of voided flat plate slabs was reinvented – by making use of plastic void formers, „genuine“ void former building became possible.